1. Field of the Invention
With regard to the classification of art, this invention is believed to be found in the general class entitled "Material or Article Handling", and more particularly to the subclasses pertaining to the lineal vertical movement of a load support. This apparatus also provides for the elevation, as well as the specific positioning of the load support about a vertical axis.
2. Description of the Related Art
The lifting of receptacles such as containers, drums and the like is the subject of my U.S. Pat. No. 5,344,275, issued Sep. 06, 1994 my U.S. Pat. No. 5,205,699, issued Apr. 27, 1993; my U.S. Pat. No. 4,797,050 issued on Jan. 10, 1989; and my U.S. Pat. No. 4,954,037, issued on Sep. 04, 1990. Each of my listed and identified Applications and Patents are soley owned by me.
U.S. Pat. Nos. 4,797,050 and 4,954,037 are directed to and teach the use of a camming trackway to provide the tilting action of the cradle. The degree of the tilting action is dependent on the magnitude of the lift. U.S. Pat. No. 5,205,699 discloses a lifting apparatus which teaches the independent lifting and tilting of drums. Each of my listed patents show the lifting apparatus to be of a mobile type. This mobility is very important in many applications, but places unwanted lifting and loading limitations for other lifting applications.
My U.S. Pat. No. 5,344,275 discloses a lifting apparatus which is of a stationary type. This lifting apparatus, employs the use of a conventional gear reducer or linear actuator. In many applications of a lifting apparatus, these type of drives are objected to due to load carrying ability and/or the leakage of fluids.
Most known commercial apparatus include a hydraulically operated cylinder to provide the lift for the support. These hydraulic cylinders require a hydraulic control system which is also subject to leakage. The space requirements and the leakage potential makes the use of hydraulic cylinders undesireable. Any leakage problems are unwelcome in those industries which manufacture pharmaceuticals and/or food products.
The present invention overcomes the problems associated with the known prior art by using a lifting means which has increased lifting capacity while minimizing the leakage of contaminants into the environment. The present invention also discloses the use of a reinforced column member. In one aspect of the invention, a safety device is an integral part of the reinforcement.
This present invention is particularly suitable for use in conjunction with fluid bed drying systems used in edible product industries. The present invention is adaptable to various lifting heights; load configurtions; and capacities.